Help Design a Human-Powered Helicopter

[PedalPower]

EDIT: Link correction noted.

What does that design have to do with the human powered helicopter? That's a time machine.

So does your every reply come in the form of cynical metanoia, or can you take a joke?

 

[Phrak]

"cynical metanoia" has a certain ring to it, jarednjames. Maybe Greg will let me change my screen name. Cynical_metanoid, perhaps. Of course you get first dibs, all things being fair.

 

[JaredJames]

"cynical metanoia" has a certain ring to it, jarednjames. Maybe Greg will let me change my screen name. Of course you get first dibs, all things being fair.

I want to say 'oxymoron' but I can't work out what "metanoia" is. Only some sketchy definitions floating around.

 

[Phrak]

I want to say 'oxymoron' but I can't work out what "metanoia" is. Only some sketchy definitions floating around.

I dunno. but it's got to good if PeddlePower came up with it.

 

[jeff kimathi]

pedalpower av read thru your comment n all i can tell you is that sometimes it takes one own effort without any much consultations to succeed in something especially these science related projects...i prefer you work it out practically n rely on the outcomes of your project to reason out the next move or your next modifications simply because critics will always out shine the kudos in real life situations....i to am in the race to trying this task i decided to do my own design n try it to make the next move from my results simply because there are those who think they are more learned thus tend to look down to others which is a great threat to your success...av done my design with my colleagues n made the necessary parts n we are awaiting the assembly n then the trial of the machine...i mean no offense at all to anyone of you registered in this forum...so go for what you think is right n let the outcomes determine your rights n wrongs

 

[Sum1]

Yesterday student engineers from Maryland University were testing for the first time their quad-rotor human powered helicopter "Gamera" -after nearly 3 years of development. They will continue their tests today too and there will be a live stream.

promo:
http://www.youtube.com/watch?v=uT4y4xb2UYI&playnext=1&list=PL342EC9DE5332F42F

preparation:


yesterday's attempt:
a)short:
http://www.youtube.com/watch?v=A_bLNHr6qPU&feature=related

b)long: The whole 3h video capture from yesterday's live stream (needs Silverlight):
http://lecture.umd.edu/detsmediasite/SilverlightPlayer/Default.aspx?peid=dae7b8b7686a4639a0faa0f58ebd08651d

Website:
http://www.newsdesk.umd.edu/bigissues/release.cfm?ArticleID=2424"

EDIT: Today's live link (it has started a while ago):
http://lecture.umd.edu/detsmediasite/SilverlightPlayer/Default.aspx?peid=25e3de8c875444169b873aecaa9f04731d

 

[whynottry]

I believe that rpms overcome weight. All of the "successful" designs have focused on very low weight materials but they cannot produce high rpm of the rotor. If the rotor is a smooth disc that can deform into a lift producing rotor then a much-higher-than-needed rpm can be achieved before it starts moving air.

 

[HowlerMonkey]

They need to change the powerplant's (awesome blonde chick) indexing between the pedals and the hand crank as well as change how her posture is aligned with the force she is exerting.

They could also make far more use of her power if they added as large a diameter flywheel to the pedal crank assembly.

It could be very light with most of it's mass concentrated on the outer diameter.

As it is now, much of the energy is being used up by flex.

 

[whynottry]

flywheel equals weight. not going to happen.

 

[HowlerMonkey]

When you watch the video, it is easy to see how jerky the application of power is and the fact that the rapid acceleration and deceleration of the cranking motion is being absorbed by the structure rather than being applied to the props.

It only takes a couple of pounds to make a flywheel which has mass concentrated on outside diameter that would smooth out her pedaling and recover the lost energy.

Since the average human varys 1 or 2 (maybe more) pounds from day to day and the fact that this girl not fully shreaded, I think it would benefit far more than detract.

 

[KyleFoster]

ok first off i didnt read every post. I am an Airframe and Powerplant mechanic, certified to work on anything that can fly and is certificated by the FAA.

Normal helicopters have around a 30 foot rotor diameter with the blades being approximately 15 feet long and around 1 foot wide. Normal rotor speeds on most helicopters is around 390 rpm's. To produce enough lift to lift a 500 pound helicopter with a ~200 pound pilot you would need about 200 rpm's of rotor speed.

Through gearing and designing a working flight control system you could do it with a normal person working the controls and pedals. Remember work smarter not harder.

With 4 axis controls it could be done.

If you build the frame from Plastic Tubing it would be strong enough and light enough for a short flight, just secure the glue joints with screws to increase the strength.

If you use gearing like a 18 speed bike to drive the main rotor and have a shaft go from the main "gearbox" to the tail gear it would be easy enough for a person of normal physical abilities to power it, and with the 4 axis controls you can regulate the amount of thrust and you will be able to keep it within the "square" so to speak.

The design would end up looking more like a modern helicopter than a weird science project gone bad.

So this being said...it would be possible to fly it across the channel if you have someone that knows how to fly it right since once its in flight you could basically autorotate, no power, for a certain distance then apply power climb to a few hundred feet and auto rotate again, the light weight of the frame and the aerodynamics of the blades would keep the aircraft in flight like a glider over longer distances.

Sorry for the long post.

 

[HowlerMonkey]

Can you help me index the PRTs of a wright 3350?

I'm a bit rusty on the radials.

 

[KyleFoster]

I have very limited experience on radial engines...most of my experience is on turbine helicopters ( bell 206 and UH60 blackhawk)

 

[HowlerMonkey]

I was lucky to get my A&P back when radials were still part of the program.

 

[Victorymike18]

They need to change the powerplant's (awesome blonde chick) indexing between the pedals and the hand crank as well as change how her posture is aligned with the force she is exerting.

They could also make far more use of her power if they added as large a diameter flywheel to the pedal crank assembly.

It could be very light with most of it's mass concentrated on the outer diameter.

As it is now, much of the energy is being used up by flex.

Agreed on all points (maybe not so much on the flywheel though).

From my experience with bicycles (I do have a fair amount) I agree that the whole seating position, and the initial driveline have a lot of room for improvement. There is a lot of flexing and what appears to be chain slap going on. If they spent some time with a quality cycle shop and fitter, they could certainly make a difference in getting it off the ground.

I recall reading from an article on human power that our muscles are at peak efficiency/power when contracting quickly at low load. So while it's good that she is working at a high RPM when it starts to lift off the ground, I'd venture to say her motions are too frantic and unbalanced at that point.

 

[Victorymike18]

Another point which I just thought of: I could certainly be wrong, but aren't there more effective ways to use a human's arm power?

When I think of using my arms powerfully, the last thing I think of would be making a pedaling motion in front of me. Rather, I would think that a rowing motion, or pulling your arms towards your chest is the best way to use those muscles...

I'm sure they could come up with some type of ratcheting chain drive for the arms, to mate with the pedal cranks...

 

[Victorymike18]

I was hoping someone would chime-in regarding my post above... Has this project ended?

I really think there is room for improvement in better-utilizing her arm power.

 

[aeroLBM]

Still pedaling the arms, but Gamera II flew 50 seconds June 21st. I think they are planning another attempt in August 2012.

http://www.agrc.umd.edu/gamera/

 

[Mech_Engineer]

Cool achievement, but let's be honset it's still well within the ground effect. It seems to me this is more accurately described as a human-powered hovercraft or ground-effect vehicle...

 

[aeroLBM]

8+ feet and 65 seconds achieved, but in separate flights.

http://www.youtube.com/user/TeamGameraHPH